CVE-2019-6726

WP Fastest Cache <= 0.8.9.0 - Directory Traversal to Arbitrary File Deletion

2022-01-24 00:00
Sebastian Neef

Strategic Overview

Status
Patched in 0.8.9.1
Affected Plugin
WP Fastest Cache – WordPress Cache Plugin
Affected Version
<= 0.8.9.0
CVSS
6.5Medium
Weakness type
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CVE
CVE-2019-6726
View all WP Fastest Cache – WordPress Cache Plugin vulnerabilities

At a glance

CVE-2019-6726 is a medium-severity Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in the WP Fastest Cache WordPress plugin, affecting versions <= 0.8.9.0. It carries a CVSS score of 6.5 (reachable over the network; high availability impact). Exploitation requires no authentication. The issue is fixed in version 0.8.9.1; sites on affected versions should update now. Disclosed January 2022, reported by Sebastian Neef.

Vulnerability Overview

The WP Fastest Cache plugin through 0.8.9.0 for WordPress allows remote attackers to delete arbitrary files because wp_postratings_clear_fastest_cache and rm_folder_recursively in wpFastestCache.php mishandle ../ in an HTTP Referer header.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on availability.

CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Reaching this weakness in WP Fastest Cache <= 0.8.9.0 takes a caller who can reach the endpoint. Path traversal happens when user-controlled text is used to build a filesystem path without being constrained to an intended directory, so sequences like ../ walk the resolved path somewhere else.

Depending on the operation, it means reading files outside the intended folder — wp-config.php being the usual target — or writing to and deleting paths the web server can touch. For WP Fastest Cache the fix is 0.8.9.1: builds <= 0.8.9.0 are affected, anything from 0.8.9.1 onward is not.

Remediation

Update to version 0.8.9.1, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to WP Fastest Cache: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: WP Fastest Cache 0.8.9.1 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2019-6726https://www.wordfence.com/threat-intel/vulnerabilities/id/6d1ad409-d5d3-4231-9a7c-de881c7b9de2https://nvd.nist.gov/vuln/detail/CVE-2019-6726

Related records

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